<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>13.boolean实例操作</title>
</head>

<body>
  <script>
    while (true) {
      let n = prompt("请输入后盾人成立年份").trim();
      if (!n) continue;
      alert(n == 2010 ? "回答正确" : "答案错误！看看官网了解下");
      break;
    }
  </script>
</body>

</html>